Graduate Theses & Dissertations

Neolithic Resource Use and Adaptation in the Eastern Gobi Desert
Stone axes and adzes first appeared in the eastern Gobi Desert at 8.0 cal BP and were incorporated into the technological package. At the same time, changes in local ecological conditions reflect a transition from continuous grass/shrub-steppe across the Mongolian Plateau to the development of dispersed patches of dune-field wetland oases and high-elevation forests. This thesis focuses on exploring the adoption and function of axes and adzes in the eastern Gobi Desert and their relationship to the development of these new forested ecologies. Using an experimental and use-wear approach, I analyze 29 axes and adzes from four sites in the eastern Gobi Desert of Mongolia and Inner Mongolia. Results indicate that axes and adzes were primarily used for woodworking but include other activities. Furthermore, the adoption and manufacture of axes and adzes represent an increasing investment in producing formal technologies as resources within these new diverse ecological patches were intensively utilized. Author Keywords: Adaptation, Axes and Adzes, Eastern Gobi Desert, Neolithic, Technological Intensification, Use-Wear
Contemporary adaptive shifts in the physiology and life history of Pumpkinseed (Lepomis gibbosus) introduced into a warm climate
Contemporary evolution has the potential to help limit the biological impact of rapidly changing climates, however it remains unclear whether wild populations can respond quickly enough for such adaptations to be effective. In this thesis, I used the introduction of native North American Pumpkinseed (Lepomis gibbosus) into the milder climate of Europe over 140 years ago, as a 'natural' experiment to test for contemporary evolution to a change in climate in wild populations. In 2008, four outdoor pond colonies were established in central Ontario using adult Pumpkinseed from two native Canadian populations, and two non-native populations from northeastern Spain. By raising native and non-native Pumpkinseed within a common environment, this design minimized the impact of phenotypic plasticity on differential trait expression, and allowed me to interpret differences in the phenotype among pond-reared Pumpkinseed as evidence of genetic differences among populations. I demonstrated that Canadian and Spanish Pumpkinseed have similar thermal physiology except when acclimated to seasonally warm temperatures; trait differences are consistent with Spanish Pumpkinseed being better adapted to a warmer climate. Populations also had similar overwintering ecology, however some differences, such as higher survival under starvation conditions and greater energetic benefits associated with winter feeding, indicated that Canadian populations are better adapted to harsh winter conditions typical of the native range. Finally, I determined that the relatively fast life history expressed in wild European Pumpkinseed is largely driven by plastic responses to the local environment; however, the higher reproductive investment by European populations has a genetic basis. Most climate change research considers taxa that are expected to be negatively impacted by warming: my research demonstrates that even warm-tolerant taxa that are unlikely to experience strong climatic selective forces can respond to a warming environment through evolutionary changes. The potential for adaptive contemporary evolution in warm-tolerant taxa should be taken into account when predicting future ecosystem effects of climate change, and when planning management strategies for species introduced into novel climates. Author Keywords: climate change, contemporary evolution, fish, non-native species, thermal biology, winter ecology
Eco-evolutionary Dynamics in a Commercially Exploited Freshwater Fishery
Fisheries assessment and management approaches have historically focused on individual species over relatively short timeframes. These approaches are being improved upon by considering the potential effects of both broader ecological and evolutionary processes. However, only recently has the question been raised of how ecological and evolutionary processes might interact to further influence fisheries yield and sustainability. My dissertation addresses this gap in our knowledge by investigating the role of eco-evolutionary dynamics in a commercially important lake whitefish fishery in the Laurentian Great Lakes, a system that has undergone substantial ecosystem change. First, I link the timing of large-scale ecological change associated with a species invasion with shifts in key density-dependent relationships that likely reflect declines in the population carrying capacity using a model selection approach. Then, using an individual-based model developed for lake whitefish in the southern main basin of Lake Huron, I demonstrate how ecosystem changes that lower growth and recruitment potential are predicted to reduce population productivity and sustainable harvest rates through demographic and plastic mechanisms. By further incorporating an evolutionary component within an eco-genetic model, I show that ecological conditions also affect evolutionary responses in maturation to harvest by altering selective pressures. Finally, using the same eco-genetic model, I provide a much-needed validation of the robustness of the probabilistic maturation reaction norm (PMRN) approach, an approach that is widely used to assess maturation and infer its evolution, to ecological and evolutionary processes experienced by exploited stocks in the wild. These findings together highlight the important role that ecological conditions play, not only in determining fishery yield and sustainability, but also in shaping evolutionary responses to harvest. Future studies evaluating the relative effects of ecological and evolutionary change and how these processes interact in harvested populations, especially with respect to freshwater versus marine ecosystems, could be especially valuable. Author Keywords: Coregonus clupeaformis, density-dependent growth, fisheries-induced evolution, individual-based eco-genetic model, Lake Huron, stock-recruitment
successful invader in expansion
Researchers have shown increasing interest in biological invasions for the associated ecological and economic impacts as well as for the opportunities they offer to study the mechanisms that induce range expansion in novel environments. I investigated the strategies exhibited by invasive species that facilitate range expansion. Invasive populations exhibit shifts in life-history strategy that may enable appropriate responses to novel biotic and abiotic factors encountered during range expansion. The spatio-temporal scales at which these shifts occur are largely unexplored. Furthermore, it is not known whether the observed dynamic shifts represent a consistent biological response of a given species to range shifts, or whether the shifts are affected by the abiotic characteristics of the new systems. I examined the life-history responses of female round gobies Neogobius melanastomus across fine and coarser spatial scales behind the expansion front and investigated whether invasive populations encountering different environmental conditions (Ontario vs France) exhibited similar life-history shifts. In both study systems, I found an increase in reproductive investment at invasion fronts compared to longer established areas at coarse and fine scales. The results suggest a similar response to range shifts, or a common invasion strategy independent of environmental conditions experienced, and highlight the dynamic nature of an invasive population’s life history behind the invasion front. The second part of my research focused on the development of an appropriate eDNA method for detecting invasive species at early stages of invasion to enable early detection and rapid management response. I developed a simple, inexpensive device for collecting water samples at selected depths for eDNA analysis, including near the substrate where eDNA concentration of benthic species is likely elevated. I also developed a protocol to optimise DNA extraction from water samples that contain elevated concentration of inhibiters, in particular near-bottom samples. Paired testing of eDNA and conventional surveys was used to monitor round goby expansion along its invasion pathway. Round gobies were detected in more sites with eDNA, permitting earlier, more accurate, upstream detection of the expansion front. My study demonstrated the accuracy and the power of using eDNA survey method to locate invasion fronts. Author Keywords: Age-specific reproductive investment, DNA extraction, Energy allocation, Fecundity, Invasion front, Range expansion
Lithic Raw Material Characterization and Technological Organization of a Late Archaic Assemblage from Jacob Island, Kawartha Lakes, Ontario
The objective of this thesis is to document and characterize the raw material and technological organization of a Late Archaic assemblage from Jacob Island, 1B/1C area (collectively referred to as BcGo-17), Peterborough County, Kawartha Lakes, Ontario. The purpose of this research is to gain a greater understanding of the Late Archaic period in central Ontario; particularly information on locally available raw material types (i.e., Trent Valley cherts) and regional interaction. My aim is to define the range of materials exploited for stone tool production and use, and to explore how variation in material relates to variation in economic strategies; I also complete a basic technological study. The collected data is then compared to temporally and geographically similar sites, and used to interpret possible relationships between acquisition practices, technology choices, and mobility. It was found that although the assemblage agrees with some of the mobility and raw material utilization models from south-western Ontario, many do not explain what was occurring on Jacob Island. Author Keywords: Archaic, Lithic Economic Strategies, Lithic Raw Material, Lithic Technology, Ontario Archaeology, Trent Valley
Geospatial Analysis of Late Paleoindan Hi-Lo Points in Ontario and New York
This thesis analyzes variability in a sample (n=302) of late Paleoindian Hi-Lo points from Ontario and New York. Biface variability is recorded using landmark geometric morphometrics. Raw material data is used to assess Hi-Lo toolstone usage patterns and the impact of raw material constraints on manufacture. Statistical analyses are used to assess patterning of variability in space. Spatial results are interpreted using cultural transmission theory in terms of their implications for the geographic scale of social learning among Hi-Lo knappers. Results of the spatial analyses are related to theory about hunter-gatherer social networks in order to understand the effects of hypothesized settling in processes on late Paleoindian knappers. Results indicate random spatial patterning of Hi-Lo variability. The absence of spatial autocorrelation for Hi-Lo size indicates that settling in processes were not sufficiently pronounced during the late Paleoindian period to manifest as inter-regional variability within the Hi-Lo type. Author Keywords: Biface Variability, Cultural Transmission, Geometric Morphometrics, Hi-Lo, Late Paleoindian, Ontario
Late Epigravettian Resource Exploitation in the Southern Pre-Alpine Region
This study examines the foraging strategies employed by Late Epigravettian occupants at Riparo Tagliente, Italy. The study sample is composed of highly fragmented macrofaunal remains recovered from a single stratigraphic layer (layer 617) located at the cave border in the southern portion of the site. Models derived from foraging theory, chiefly the Central Place Forager Prey Choice Model, are applied to interpret the pattern of faunal exploitation. Red deer (Cervus elaphus) is the most commonly identified species in the sample, followed by roe deer (Capreolus capreolus) and wild boar (Sus scrofa). The faunal analysis suggests that the site occupants focused their foraging efforts in lower–altitude resource patches at short travel distances. The distribution and composition of the sample indicates that bone may have been used as a fuel source in this area. Author Keywords: Archaeozoology, Foraging Theory, Taphonomy, Upper Paleolithic
Ecological and morphological traits that affect the fitness and dispersal potential of Iberian pumpkinseed (Lepomis gibbosus)
The Pumpkinseed (Lepomis gibbosus) is a sunfish that is endemic to eastern portions of Canada and the United States. During the late 19th century, the species was introduced into Europe, and it is now present in over 28 countries. Previous attempts to determine the characteristics that can predict the spread of non-indigenous species have been largely unsuccessful, but new evidence suggests that phenotypic plasticity may help to explain the dispersal and range expansion of some organisms. Experimental comparisons on lower-order taxa have revealed that populations from areas outside of their native range are capable of exhibiting stronger levels of phenotypic plasticity than counterparts from their source of origin. Using Pumpkinseed, I conducted the first native/non- native comparison of phenotypic plasticity in a vertebrate. Progeny from adult Pumpkinseed collected in Ontario, Canada and the Iberian Peninsula (Spain) were reared under variable water velocities, habitat type and competitive pressures, three ecological factors that may affect the dispersal potential of fishes introduced into novel aquatic systems. Differences in phenotypic plasticity, assessed from a morphological perspective, were compared among populations using a traditional distance-based approach. All populations exhibited divergent morphological traits that appeared to be inherited over successive generations. In each experiment, all populations responded to environmental change by developing internal and external morphological forms that, in related taxa, enhance and facilitate foraging and navigation; however, non-native populations always exhibited an overall lower level of phenotypic plasticity. Pumpkinseed from non-native areas may have exhibited a reduction in phenotypic plasticity because of population-based differences. Nevertheless, all Pumpkinseed populations studied were capable of exhibiting phenotypic plasticity to novel environmental conditions, and develop morphological characteristics that may enhance fitness and dispersal in perturbed areas. Author Keywords: Invasive species, Morphology, Phenotypic plasticity, Pumpkinseed sunfish, Reaction norm
VISUAL INFORMATION-PROCESSING AND THE EVOLUTION OF FLAKE MAKING SKILL
Flaked stones tools are the oldest and longest persisting human cultural remains. Some of these tools were made by hominins who were not anatomically or cognitively modern. My thesis uses an eye-tracking device, developed by psychology, to study modern day novice and expert tool making. By comparing these two groups I was able to characterize the behaviours that lead to successful flake making, and furthermore make inferences about the cognitive capacities that hominins would have had to have to have been successful themselves. This study suggests limited engagement of short-term memory and problem solving skills, which is consistent with other studies. However, this study seems to refute the hypothesis that improvements in hand-eye coordination alone account for the rise of flaked stone technology. My thesis also shows that eye-tracking is a fruitful way to study flake making and, based on my research, I propose several future directions of study. Author Keywords: Eye-tracking, Human Evolution, Knapping, Oldowan, Skill
An Ecological Analysis of Late Woodland Settlement Patterns in the Rouge River Watershed, Southern Ontario
This thesis seeks to understand the influences of environmental variables on site location selection during the Late Woodland period (ca. A.D. 1000-1650) in south-central Ontario, specifically variables considered to be favourable to maize agriculture. Four analyses were undertaken: a geographic information system (GIS) comparative analysis of Late Woodland sites compared to random points; population estimates of four sites for which settlement pattern data was available; maize consumption estimates for these same sites, and; a maize resources catchment analysis of these sites. The analysis conducted did not produce conclusive results to answer questions related to maize-driven site selection, however it did show that requirements for maize resources at these sites could have been met in catchment areas of a 500 m radius, in one case in 250m. The results led to an important question for future research: if agricultural needs were not driving settlement location selection in this area, what was? Author Keywords: Environmental Modeling, GIS, Late Woodland, Maize Agriculture, Movement of Communities, Ontario Archaeology
Critical Analysis of the Adoption of Maize in Southern Ontario and its Spatial, Demographic, and Ecological Signatures
This thesis centers on analyzing the spatial, temporal, and ecological patterns associated with the introduction of maize horticulture into Southern Ontario - contextualized against social and demographic models of agricultural transition. Two separate analyses are undertaken: a regional analysis of the spread of maize across the Northeast using linear regression of radiocarbon data and a standard Wave of Advance model; and a local analysis of village locational trends in Southern Ontario using a landscape ecological framework, environmental data and known village sites. Through the integration of these two spatial and temporal scales of analysis, this research finds strong support for both migration and local development. A third model of competition and coalescence is presented to describe the patterning in the data. Author Keywords: Demographic Modeling, Environmental Modeling, Geostastical Analysis, Maize, Ontario Archaeology, Spread of Agriculture

Search Our Digital Collections

Query

Enabled Filters

  • (-) ≠ Farell
  • (-) ≠ Bell
  • (-) ≠ Master of Science
  • (-) = Fox

Filter Results

Date

2009 - 2029
(decades)
Specify date range: Show
Format: 2019/11/19

Author Last Name

Show more

Last Name (Other)

Show more

Degree Discipline

Subject (Topic)